In semiconductor chip manufacturing, pre-packaging processes may include a variety of operations including, for example, semiconductor substrate mounting, wafer sawing, die separation, die transfer, die attach, and the like. These operations involve physically manipulating chips and therefore require the utmost care, as damaged chips increase processing costs and reduce yield. Incidentally, semiconductor technology continues to evolve in such a way that chip substrates have become more and more fragile (e.g., thinner), thus making chips incorporating those substrates more susceptible to fractures.
In a typical pre-packaging operation, after wafers are sorted, they are each mounted on an adhesive tape or film. The adhesive tape may provide support for the wafers during singulation, die transfer, or die attach operations. During the singulation operation, for example, a wafer saw or other cutting mechanism separates individual dies from the wafer while leaving them bonded onto the adhesive tape.
After singulation, a die attach operation or a sorting operation removes individual die from the adhesive tape or film and attaches them to a packaging substrate (e.g., a leadframe), or transfers them to another carrier for storage and later use. To that end, a conventional die bonder ejector system may include rod(s) or pin(s) configured to push each chip up and to separate it from the tape, thereby facilitating subsequent transport of the die by a pickup tool or the like. The inventors hereof have determined, however, that the use of ejector pins causes yet additional stresses on the dies, further increasing the risk of damage.